Stability of the output energy of pulsed solid-state lasers passively Q-switched using LiF crystals containing [IMG align=ABSMIDDLE alt=$F^-_2$]f2-i[/IMG] color centers

An investigation was made of the stability of the output energy of passively Q-switched pulsed neodymium-doped GLS-24P glass and YAG:Nd solid-state lasers (the widths of the emission spectra at the second harmonic frequency were 9 and 0.2 cm^–1, respectively) as a function of the stability of the pump source, the resonator length, and the number of pulses. The dependence of the output energy on the pump energy was determined in the range between the thresholds of the first and second pulses. It was shown experimentally that the short-term stability of the output energy (the relative variance from a sample of 500 pulses) could be better than 0.2%. Under the experimental conditions the drop in the output energy after 18 X 10³ pulses did not exceed 10%. This drop was attributed to decay of [IMG align=ABSMIDDLE alt=$F^-_2$]f2-i[/IMG] color centers under the action of high-power laser radiation and to an increase in the initial transmission of the switch.